1 //===-- llvm/Constants.h - Constant class subclass definitions --*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
11 /// This file contains the declarations for the subclasses of Constant,
12 /// which represent the different flavors of constant values that live in LLVM.
13 /// Note that Constants are immutable (once created they never change) and are
14 /// fully shared by structural equivalence. This means that two structurally
15 /// equivalent constants will always have the same address. Constant's are
16 /// created on demand as needed and never deleted: thus clients don't have to
17 /// worry about the lifetime of the objects.
19 //===----------------------------------------------------------------------===//
21 #ifndef LLVM_IR_CONSTANTS_H
22 #define LLVM_IR_CONSTANTS_H
24 #include "llvm/ADT/APFloat.h"
25 #include "llvm/ADT/APInt.h"
26 #include "llvm/ADT/ArrayRef.h"
27 #include "llvm/IR/Constant.h"
28 #include "llvm/IR/DerivedTypes.h"
29 #include "llvm/IR/OperandTraits.h"
40 struct ConstantExprKeyType;
41 template <class ConstantClass> struct ConstantAggrKeyType;
43 //===----------------------------------------------------------------------===//
44 /// This is the shared class of boolean and integer constants. This class
45 /// represents both boolean and integral constants.
46 /// @brief Class for constant integers.
47 class ConstantInt : public Constant {
48 void anchor() override;
49 void *operator new(size_t, unsigned) = delete;
50 ConstantInt(const ConstantInt &) = delete;
51 ConstantInt(IntegerType *Ty, const APInt& V);
54 // allocate space for exactly zero operands
55 void *operator new(size_t s) {
56 return User::operator new(s, 0);
59 static ConstantInt *getTrue(LLVMContext &Context);
60 static ConstantInt *getFalse(LLVMContext &Context);
61 static Constant *getTrue(Type *Ty);
62 static Constant *getFalse(Type *Ty);
64 /// If Ty is a vector type, return a Constant with a splat of the given
65 /// value. Otherwise return a ConstantInt for the given value.
66 static Constant *get(Type *Ty, uint64_t V, bool isSigned = false);
68 /// Return a ConstantInt with the specified integer value for the specified
69 /// type. If the type is wider than 64 bits, the value will be zero-extended
70 /// to fit the type, unless isSigned is true, in which case the value will
71 /// be interpreted as a 64-bit signed integer and sign-extended to fit
73 /// @brief Get a ConstantInt for a specific value.
74 static ConstantInt *get(IntegerType *Ty, uint64_t V,
75 bool isSigned = false);
77 /// Return a ConstantInt with the specified value for the specified type. The
78 /// value V will be canonicalized to a an unsigned APInt. Accessing it with
79 /// either getSExtValue() or getZExtValue() will yield a correctly sized and
80 /// signed value for the type Ty.
81 /// @brief Get a ConstantInt for a specific signed value.
82 static ConstantInt *getSigned(IntegerType *Ty, int64_t V);
83 static Constant *getSigned(Type *Ty, int64_t V);
85 /// Return a ConstantInt with the specified value and an implied Type. The
86 /// type is the integer type that corresponds to the bit width of the value.
87 static ConstantInt *get(LLVMContext &Context, const APInt &V);
89 /// Return a ConstantInt constructed from the string strStart with the given
91 static ConstantInt *get(IntegerType *Ty, StringRef Str,
94 /// If Ty is a vector type, return a Constant with a splat of the given
95 /// value. Otherwise return a ConstantInt for the given value.
96 static Constant *get(Type* Ty, const APInt& V);
98 /// Return the constant as an APInt value reference. This allows clients to
99 /// obtain a copy of the value, with all its precision in tact.
100 /// @brief Return the constant's value.
101 inline const APInt &getValue() const {
105 /// getBitWidth - Return the bitwidth of this constant.
106 unsigned getBitWidth() const { return Val.getBitWidth(); }
108 /// Return the constant as a 64-bit unsigned integer value after it
109 /// has been zero extended as appropriate for the type of this constant. Note
110 /// that this method can assert if the value does not fit in 64 bits.
111 /// @brief Return the zero extended value.
112 inline uint64_t getZExtValue() const {
113 return Val.getZExtValue();
116 /// Return the constant as a 64-bit integer value after it has been sign
117 /// extended as appropriate for the type of this constant. Note that
118 /// this method can assert if the value does not fit in 64 bits.
119 /// @brief Return the sign extended value.
120 inline int64_t getSExtValue() const {
121 return Val.getSExtValue();
124 /// A helper method that can be used to determine if the constant contained
125 /// within is equal to a constant. This only works for very small values,
126 /// because this is all that can be represented with all types.
127 /// @brief Determine if this constant's value is same as an unsigned char.
128 bool equalsInt(uint64_t V) const {
132 /// getType - Specialize the getType() method to always return an IntegerType,
133 /// which reduces the amount of casting needed in parts of the compiler.
135 inline IntegerType *getType() const {
136 return cast<IntegerType>(Value::getType());
139 /// This static method returns true if the type Ty is big enough to
140 /// represent the value V. This can be used to avoid having the get method
141 /// assert when V is larger than Ty can represent. Note that there are two
142 /// versions of this method, one for unsigned and one for signed integers.
143 /// Although ConstantInt canonicalizes everything to an unsigned integer,
144 /// the signed version avoids callers having to convert a signed quantity
145 /// to the appropriate unsigned type before calling the method.
146 /// @returns true if V is a valid value for type Ty
147 /// @brief Determine if the value is in range for the given type.
148 static bool isValueValidForType(Type *Ty, uint64_t V);
149 static bool isValueValidForType(Type *Ty, int64_t V);
151 bool isNegative() const { return Val.isNegative(); }
153 /// This is just a convenience method to make client code smaller for a
154 /// common code. It also correctly performs the comparison without the
155 /// potential for an assertion from getZExtValue().
156 bool isZero() const {
160 /// This is just a convenience method to make client code smaller for a
161 /// common case. It also correctly performs the comparison without the
162 /// potential for an assertion from getZExtValue().
163 /// @brief Determine if the value is one.
168 /// This function will return true iff every bit in this constant is set
170 /// @returns true iff this constant's bits are all set to true.
171 /// @brief Determine if the value is all ones.
172 bool isMinusOne() const {
173 return Val.isAllOnesValue();
176 /// This function will return true iff this constant represents the largest
177 /// value that may be represented by the constant's type.
178 /// @returns true iff this is the largest value that may be represented
180 /// @brief Determine if the value is maximal.
181 bool isMaxValue(bool isSigned) const {
183 return Val.isMaxSignedValue();
185 return Val.isMaxValue();
188 /// This function will return true iff this constant represents the smallest
189 /// value that may be represented by this constant's type.
190 /// @returns true if this is the smallest value that may be represented by
192 /// @brief Determine if the value is minimal.
193 bool isMinValue(bool isSigned) const {
195 return Val.isMinSignedValue();
197 return Val.isMinValue();
200 /// This function will return true iff this constant represents a value with
201 /// active bits bigger than 64 bits or a value greater than the given uint64_t
203 /// @returns true iff this constant is greater or equal to the given number.
204 /// @brief Determine if the value is greater or equal to the given number.
205 bool uge(uint64_t Num) const {
206 return Val.getActiveBits() > 64 || Val.getZExtValue() >= Num;
209 /// getLimitedValue - If the value is smaller than the specified limit,
210 /// return it, otherwise return the limit value. This causes the value
211 /// to saturate to the limit.
212 /// @returns the min of the value of the constant and the specified value
213 /// @brief Get the constant's value with a saturation limit
214 uint64_t getLimitedValue(uint64_t Limit = ~0ULL) const {
215 return Val.getLimitedValue(Limit);
218 /// @brief Methods to support type inquiry through isa, cast, and dyn_cast.
219 static bool classof(const Value *V) {
220 return V->getValueID() == ConstantIntVal;
225 //===----------------------------------------------------------------------===//
226 /// ConstantFP - Floating Point Values [float, double]
228 class ConstantFP : public Constant {
230 void anchor() override;
231 void *operator new(size_t, unsigned) = delete;
232 ConstantFP(const ConstantFP &) = delete;
233 friend class LLVMContextImpl;
235 ConstantFP(Type *Ty, const APFloat& V);
237 // allocate space for exactly zero operands
238 void *operator new(size_t s) {
239 return User::operator new(s, 0);
242 /// Floating point negation must be implemented with f(x) = -0.0 - x. This
243 /// method returns the negative zero constant for floating point or vector
244 /// floating point types; for all other types, it returns the null value.
245 static Constant *getZeroValueForNegation(Type *Ty);
247 /// get() - This returns a ConstantFP, or a vector containing a splat of a
248 /// ConstantFP, for the specified value in the specified type. This should
249 /// only be used for simple constant values like 2.0/1.0 etc, that are
250 /// known-valid both as host double and as the target format.
251 static Constant *get(Type* Ty, double V);
252 static Constant *get(Type* Ty, StringRef Str);
253 static ConstantFP *get(LLVMContext &Context, const APFloat &V);
254 static Constant *getNegativeZero(Type *Ty);
255 static Constant *getInfinity(Type *Ty, bool Negative = false);
257 /// isValueValidForType - return true if Ty is big enough to represent V.
258 static bool isValueValidForType(Type *Ty, const APFloat &V);
259 inline const APFloat &getValueAPF() const { return Val; }
261 /// isZero - Return true if the value is positive or negative zero.
262 bool isZero() const { return Val.isZero(); }
264 /// isNegative - Return true if the sign bit is set.
265 bool isNegative() const { return Val.isNegative(); }
267 /// isInfinity - Return true if the value is infinity
268 bool isInfinity() const { return Val.isInfinity(); }
270 /// isNaN - Return true if the value is a NaN.
271 bool isNaN() const { return Val.isNaN(); }
273 /// isExactlyValue - We don't rely on operator== working on double values, as
274 /// it returns true for things that are clearly not equal, like -0.0 and 0.0.
275 /// As such, this method can be used to do an exact bit-for-bit comparison of
276 /// two floating point values. The version with a double operand is retained
277 /// because it's so convenient to write isExactlyValue(2.0), but please use
278 /// it only for simple constants.
279 bool isExactlyValue(const APFloat &V) const;
281 bool isExactlyValue(double V) const {
284 FV.convert(Val.getSemantics(), APFloat::rmNearestTiesToEven, &ignored);
285 return isExactlyValue(FV);
287 /// Methods for support type inquiry through isa, cast, and dyn_cast:
288 static bool classof(const Value *V) {
289 return V->getValueID() == ConstantFPVal;
293 //===----------------------------------------------------------------------===//
294 /// ConstantAggregateZero - All zero aggregate value
296 class ConstantAggregateZero : public Constant {
297 void *operator new(size_t, unsigned) = delete;
298 ConstantAggregateZero(const ConstantAggregateZero &) = delete;
300 explicit ConstantAggregateZero(Type *ty)
301 : Constant(ty, ConstantAggregateZeroVal, nullptr, 0) {}
303 // allocate space for exactly zero operands
304 void *operator new(size_t s) {
305 return User::operator new(s, 0);
308 static ConstantAggregateZero *get(Type *Ty);
310 void destroyConstant() override;
312 /// getSequentialElement - If this CAZ has array or vector type, return a zero
313 /// with the right element type.
314 Constant *getSequentialElement() const;
316 /// getStructElement - If this CAZ has struct type, return a zero with the
317 /// right element type for the specified element.
318 Constant *getStructElement(unsigned Elt) const;
320 /// getElementValue - Return a zero of the right value for the specified GEP
322 Constant *getElementValue(Constant *C) const;
324 /// getElementValue - Return a zero of the right value for the specified GEP
326 Constant *getElementValue(unsigned Idx) const;
328 /// \brief Return the number of elements in the array, vector, or struct.
329 unsigned getNumElements() const;
331 /// Methods for support type inquiry through isa, cast, and dyn_cast:
333 static bool classof(const Value *V) {
334 return V->getValueID() == ConstantAggregateZeroVal;
339 //===----------------------------------------------------------------------===//
340 /// ConstantArray - Constant Array Declarations
342 class ConstantArray : public Constant {
343 friend struct ConstantAggrKeyType<ConstantArray>;
344 ConstantArray(const ConstantArray &) = delete;
346 ConstantArray(ArrayType *T, ArrayRef<Constant *> Val);
348 // ConstantArray accessors
349 static Constant *get(ArrayType *T, ArrayRef<Constant*> V);
352 static Constant *getImpl(ArrayType *T, ArrayRef<Constant *> V);
355 /// Transparently provide more efficient getOperand methods.
356 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Constant);
358 /// getType - Specialize the getType() method to always return an ArrayType,
359 /// which reduces the amount of casting needed in parts of the compiler.
361 inline ArrayType *getType() const {
362 return cast<ArrayType>(Value::getType());
365 void destroyConstant() override;
366 void replaceUsesOfWithOnConstant(Value *From, Value *To, Use *U) override;
368 /// Methods for support type inquiry through isa, cast, and dyn_cast:
369 static bool classof(const Value *V) {
370 return V->getValueID() == ConstantArrayVal;
375 struct OperandTraits<ConstantArray> :
376 public VariadicOperandTraits<ConstantArray> {
379 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(ConstantArray, Constant)
381 //===----------------------------------------------------------------------===//
382 // ConstantStruct - Constant Struct Declarations
384 class ConstantStruct : public Constant {
385 friend struct ConstantAggrKeyType<ConstantStruct>;
386 ConstantStruct(const ConstantStruct &) = delete;
388 ConstantStruct(StructType *T, ArrayRef<Constant *> Val);
390 // ConstantStruct accessors
391 static Constant *get(StructType *T, ArrayRef<Constant*> V);
392 static Constant *get(StructType *T, ...) LLVM_END_WITH_NULL;
394 /// getAnon - Return an anonymous struct that has the specified
395 /// elements. If the struct is possibly empty, then you must specify a
397 static Constant *getAnon(ArrayRef<Constant*> V, bool Packed = false) {
398 return get(getTypeForElements(V, Packed), V);
400 static Constant *getAnon(LLVMContext &Ctx,
401 ArrayRef<Constant*> V, bool Packed = false) {
402 return get(getTypeForElements(Ctx, V, Packed), V);
405 /// getTypeForElements - Return an anonymous struct type to use for a constant
406 /// with the specified set of elements. The list must not be empty.
407 static StructType *getTypeForElements(ArrayRef<Constant*> V,
408 bool Packed = false);
409 /// getTypeForElements - This version of the method allows an empty list.
410 static StructType *getTypeForElements(LLVMContext &Ctx,
411 ArrayRef<Constant*> V,
412 bool Packed = false);
414 /// Transparently provide more efficient getOperand methods.
415 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Constant);
417 /// getType() specialization - Reduce amount of casting...
419 inline StructType *getType() const {
420 return cast<StructType>(Value::getType());
423 void destroyConstant() override;
424 void replaceUsesOfWithOnConstant(Value *From, Value *To, Use *U) override;
426 /// Methods for support type inquiry through isa, cast, and dyn_cast:
427 static bool classof(const Value *V) {
428 return V->getValueID() == ConstantStructVal;
433 struct OperandTraits<ConstantStruct> :
434 public VariadicOperandTraits<ConstantStruct> {
437 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(ConstantStruct, Constant)
440 //===----------------------------------------------------------------------===//
441 /// ConstantVector - Constant Vector Declarations
443 class ConstantVector : public Constant {
444 friend struct ConstantAggrKeyType<ConstantVector>;
445 ConstantVector(const ConstantVector &) = delete;
447 ConstantVector(VectorType *T, ArrayRef<Constant *> Val);
449 // ConstantVector accessors
450 static Constant *get(ArrayRef<Constant*> V);
453 static Constant *getImpl(ArrayRef<Constant *> V);
456 /// getSplat - Return a ConstantVector with the specified constant in each
458 static Constant *getSplat(unsigned NumElts, Constant *Elt);
460 /// Transparently provide more efficient getOperand methods.
461 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Constant);
463 /// getType - Specialize the getType() method to always return a VectorType,
464 /// which reduces the amount of casting needed in parts of the compiler.
466 inline VectorType *getType() const {
467 return cast<VectorType>(Value::getType());
470 /// getSplatValue - If this is a splat constant, meaning that all of the
471 /// elements have the same value, return that value. Otherwise return NULL.
472 Constant *getSplatValue() const;
474 void destroyConstant() override;
475 void replaceUsesOfWithOnConstant(Value *From, Value *To, Use *U) override;
477 /// Methods for support type inquiry through isa, cast, and dyn_cast:
478 static bool classof(const Value *V) {
479 return V->getValueID() == ConstantVectorVal;
484 struct OperandTraits<ConstantVector> :
485 public VariadicOperandTraits<ConstantVector> {
488 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(ConstantVector, Constant)
490 //===----------------------------------------------------------------------===//
491 /// ConstantPointerNull - a constant pointer value that points to null
493 class ConstantPointerNull : public Constant {
494 void *operator new(size_t, unsigned) = delete;
495 ConstantPointerNull(const ConstantPointerNull &) = delete;
497 explicit ConstantPointerNull(PointerType *T)
499 Value::ConstantPointerNullVal, nullptr, 0) {}
502 // allocate space for exactly zero operands
503 void *operator new(size_t s) {
504 return User::operator new(s, 0);
507 /// get() - Static factory methods - Return objects of the specified value
508 static ConstantPointerNull *get(PointerType *T);
510 void destroyConstant() override;
512 /// getType - Specialize the getType() method to always return an PointerType,
513 /// which reduces the amount of casting needed in parts of the compiler.
515 inline PointerType *getType() const {
516 return cast<PointerType>(Value::getType());
519 /// Methods for support type inquiry through isa, cast, and dyn_cast:
520 static bool classof(const Value *V) {
521 return V->getValueID() == ConstantPointerNullVal;
525 //===----------------------------------------------------------------------===//
526 /// ConstantDataSequential - A vector or array constant whose element type is a
527 /// simple 1/2/4/8-byte integer or float/double, and whose elements are just
528 /// simple data values (i.e. ConstantInt/ConstantFP). This Constant node has no
529 /// operands because it stores all of the elements of the constant as densely
530 /// packed data, instead of as Value*'s.
532 /// This is the common base class of ConstantDataArray and ConstantDataVector.
534 class ConstantDataSequential : public Constant {
535 friend class LLVMContextImpl;
536 /// DataElements - A pointer to the bytes underlying this constant (which is
537 /// owned by the uniquing StringMap).
538 const char *DataElements;
540 /// Next - This forms a link list of ConstantDataSequential nodes that have
541 /// the same value but different type. For example, 0,0,0,1 could be a 4
542 /// element array of i8, or a 1-element array of i32. They'll both end up in
543 /// the same StringMap bucket, linked up.
544 ConstantDataSequential *Next;
545 void *operator new(size_t, unsigned) = delete;
546 ConstantDataSequential(const ConstantDataSequential &) = delete;
548 explicit ConstantDataSequential(Type *ty, ValueTy VT, const char *Data)
549 : Constant(ty, VT, nullptr, 0), DataElements(Data), Next(nullptr) {}
550 ~ConstantDataSequential() { delete Next; }
552 static Constant *getImpl(StringRef Bytes, Type *Ty);
555 // allocate space for exactly zero operands.
556 void *operator new(size_t s) {
557 return User::operator new(s, 0);
561 /// isElementTypeCompatible - Return true if a ConstantDataSequential can be
562 /// formed with a vector or array of the specified element type.
563 /// ConstantDataArray only works with normal float and int types that are
564 /// stored densely in memory, not with things like i42 or x86_f80.
565 static bool isElementTypeCompatible(const Type *Ty);
567 /// getElementAsInteger - If this is a sequential container of integers (of
568 /// any size), return the specified element in the low bits of a uint64_t.
569 uint64_t getElementAsInteger(unsigned i) const;
571 /// getElementAsAPFloat - If this is a sequential container of floating point
572 /// type, return the specified element as an APFloat.
573 APFloat getElementAsAPFloat(unsigned i) const;
575 /// getElementAsFloat - If this is an sequential container of floats, return
576 /// the specified element as a float.
577 float getElementAsFloat(unsigned i) const;
579 /// getElementAsDouble - If this is an sequential container of doubles, return
580 /// the specified element as a double.
581 double getElementAsDouble(unsigned i) const;
583 /// getElementAsConstant - Return a Constant for a specified index's element.
584 /// Note that this has to compute a new constant to return, so it isn't as
585 /// efficient as getElementAsInteger/Float/Double.
586 Constant *getElementAsConstant(unsigned i) const;
588 /// getType - Specialize the getType() method to always return a
589 /// SequentialType, which reduces the amount of casting needed in parts of the
591 inline SequentialType *getType() const {
592 return cast<SequentialType>(Value::getType());
595 /// getElementType - Return the element type of the array/vector.
596 Type *getElementType() const;
598 /// getNumElements - Return the number of elements in the array or vector.
599 unsigned getNumElements() const;
601 /// getElementByteSize - Return the size (in bytes) of each element in the
602 /// array/vector. The size of the elements is known to be a multiple of one
604 uint64_t getElementByteSize() const;
607 /// isString - This method returns true if this is an array of i8.
608 bool isString() const;
610 /// isCString - This method returns true if the array "isString", ends with a
611 /// nul byte, and does not contains any other nul bytes.
612 bool isCString() const;
614 /// getAsString - If this array is isString(), then this method returns the
615 /// array as a StringRef. Otherwise, it asserts out.
617 StringRef getAsString() const {
618 assert(isString() && "Not a string");
619 return getRawDataValues();
622 /// getAsCString - If this array is isCString(), then this method returns the
623 /// array (without the trailing null byte) as a StringRef. Otherwise, it
626 StringRef getAsCString() const {
627 assert(isCString() && "Isn't a C string");
628 StringRef Str = getAsString();
629 return Str.substr(0, Str.size()-1);
632 /// getRawDataValues - Return the raw, underlying, bytes of this data. Note
633 /// that this is an extremely tricky thing to work with, as it exposes the
634 /// host endianness of the data elements.
635 StringRef getRawDataValues() const;
637 void destroyConstant() override;
639 /// Methods for support type inquiry through isa, cast, and dyn_cast:
641 static bool classof(const Value *V) {
642 return V->getValueID() == ConstantDataArrayVal ||
643 V->getValueID() == ConstantDataVectorVal;
646 const char *getElementPointer(unsigned Elt) const;
649 //===----------------------------------------------------------------------===//
650 /// ConstantDataArray - An array constant whose element type is a simple
651 /// 1/2/4/8-byte integer or float/double, and whose elements are just simple
652 /// data values (i.e. ConstantInt/ConstantFP). This Constant node has no
653 /// operands because it stores all of the elements of the constant as densely
654 /// packed data, instead of as Value*'s.
655 class ConstantDataArray : public ConstantDataSequential {
656 void *operator new(size_t, unsigned) = delete;
657 ConstantDataArray(const ConstantDataArray &) = delete;
658 void anchor() override;
659 friend class ConstantDataSequential;
660 explicit ConstantDataArray(Type *ty, const char *Data)
661 : ConstantDataSequential(ty, ConstantDataArrayVal, Data) {}
663 // allocate space for exactly zero operands.
664 void *operator new(size_t s) {
665 return User::operator new(s, 0);
669 /// get() constructors - Return a constant with array type with an element
670 /// count and element type matching the ArrayRef passed in. Note that this
671 /// can return a ConstantAggregateZero object.
672 static Constant *get(LLVMContext &Context, ArrayRef<uint8_t> Elts);
673 static Constant *get(LLVMContext &Context, ArrayRef<uint16_t> Elts);
674 static Constant *get(LLVMContext &Context, ArrayRef<uint32_t> Elts);
675 static Constant *get(LLVMContext &Context, ArrayRef<uint64_t> Elts);
676 static Constant *get(LLVMContext &Context, ArrayRef<float> Elts);
677 static Constant *get(LLVMContext &Context, ArrayRef<double> Elts);
679 /// getFP() constructors - Return a constant with array type with an element
680 /// count and element type of float with precision matching the number of
681 /// bits in the ArrayRef passed in. (i.e. half for 16bits, float for 32bits,
682 /// double for 64bits) Note that this can return a ConstantAggregateZero
684 static Constant *getFP(LLVMContext &Context, ArrayRef<uint16_t> Elts);
685 static Constant *getFP(LLVMContext &Context, ArrayRef<uint32_t> Elts);
686 static Constant *getFP(LLVMContext &Context, ArrayRef<uint64_t> Elts);
688 /// getString - This method constructs a CDS and initializes it with a text
689 /// string. The default behavior (AddNull==true) causes a null terminator to
690 /// be placed at the end of the array (increasing the length of the string by
691 /// one more than the StringRef would normally indicate. Pass AddNull=false
692 /// to disable this behavior.
693 static Constant *getString(LLVMContext &Context, StringRef Initializer,
694 bool AddNull = true);
696 /// getType - Specialize the getType() method to always return an ArrayType,
697 /// which reduces the amount of casting needed in parts of the compiler.
699 inline ArrayType *getType() const {
700 return cast<ArrayType>(Value::getType());
703 /// Methods for support type inquiry through isa, cast, and dyn_cast:
705 static bool classof(const Value *V) {
706 return V->getValueID() == ConstantDataArrayVal;
710 //===----------------------------------------------------------------------===//
711 /// ConstantDataVector - A vector constant whose element type is a simple
712 /// 1/2/4/8-byte integer or float/double, and whose elements are just simple
713 /// data values (i.e. ConstantInt/ConstantFP). This Constant node has no
714 /// operands because it stores all of the elements of the constant as densely
715 /// packed data, instead of as Value*'s.
716 class ConstantDataVector : public ConstantDataSequential {
717 void *operator new(size_t, unsigned) = delete;
718 ConstantDataVector(const ConstantDataVector &) = delete;
719 void anchor() override;
720 friend class ConstantDataSequential;
721 explicit ConstantDataVector(Type *ty, const char *Data)
722 : ConstantDataSequential(ty, ConstantDataVectorVal, Data) {}
724 // allocate space for exactly zero operands.
725 void *operator new(size_t s) {
726 return User::operator new(s, 0);
730 /// get() constructors - Return a constant with vector type with an element
731 /// count and element type matching the ArrayRef passed in. Note that this
732 /// can return a ConstantAggregateZero object.
733 static Constant *get(LLVMContext &Context, ArrayRef<uint8_t> Elts);
734 static Constant *get(LLVMContext &Context, ArrayRef<uint16_t> Elts);
735 static Constant *get(LLVMContext &Context, ArrayRef<uint32_t> Elts);
736 static Constant *get(LLVMContext &Context, ArrayRef<uint64_t> Elts);
737 static Constant *get(LLVMContext &Context, ArrayRef<float> Elts);
738 static Constant *get(LLVMContext &Context, ArrayRef<double> Elts);
740 /// getFP() constructors - Return a constant with vector type with an element
741 /// count and element type of float with the precision matching the number of
742 /// bits in the ArrayRef passed in. (i.e. half for 16bits, float for 32bits,
743 /// double for 64bits) Note that this can return a ConstantAggregateZero
745 static Constant *getFP(LLVMContext &Context, ArrayRef<uint16_t> Elts);
746 static Constant *getFP(LLVMContext &Context, ArrayRef<uint32_t> Elts);
747 static Constant *getFP(LLVMContext &Context, ArrayRef<uint64_t> Elts);
749 /// getSplat - Return a ConstantVector with the specified constant in each
750 /// element. The specified constant has to be a of a compatible type (i8/i16/
751 /// i32/i64/float/double) and must be a ConstantFP or ConstantInt.
752 static Constant *getSplat(unsigned NumElts, Constant *Elt);
754 /// getSplatValue - If this is a splat constant, meaning that all of the
755 /// elements have the same value, return that value. Otherwise return NULL.
756 Constant *getSplatValue() const;
758 /// getType - Specialize the getType() method to always return a VectorType,
759 /// which reduces the amount of casting needed in parts of the compiler.
761 inline VectorType *getType() const {
762 return cast<VectorType>(Value::getType());
765 /// Methods for support type inquiry through isa, cast, and dyn_cast:
767 static bool classof(const Value *V) {
768 return V->getValueID() == ConstantDataVectorVal;
774 /// BlockAddress - The address of a basic block.
776 class BlockAddress : public Constant {
777 void *operator new(size_t, unsigned) = delete;
778 void *operator new(size_t s) { return User::operator new(s, 2); }
779 BlockAddress(Function *F, BasicBlock *BB);
781 /// get - Return a BlockAddress for the specified function and basic block.
782 static BlockAddress *get(Function *F, BasicBlock *BB);
784 /// get - Return a BlockAddress for the specified basic block. The basic
785 /// block must be embedded into a function.
786 static BlockAddress *get(BasicBlock *BB);
788 /// \brief Lookup an existing \c BlockAddress constant for the given
791 /// \returns 0 if \c !BB->hasAddressTaken(), otherwise the \c BlockAddress.
792 static BlockAddress *lookup(const BasicBlock *BB);
794 /// Transparently provide more efficient getOperand methods.
795 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
797 Function *getFunction() const { return (Function*)Op<0>().get(); }
798 BasicBlock *getBasicBlock() const { return (BasicBlock*)Op<1>().get(); }
800 void destroyConstant() override;
801 void replaceUsesOfWithOnConstant(Value *From, Value *To, Use *U) override;
803 /// Methods for support type inquiry through isa, cast, and dyn_cast:
804 static inline bool classof(const Value *V) {
805 return V->getValueID() == BlockAddressVal;
810 struct OperandTraits<BlockAddress> :
811 public FixedNumOperandTraits<BlockAddress, 2> {
814 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(BlockAddress, Value)
817 //===----------------------------------------------------------------------===//
818 /// ConstantExpr - a constant value that is initialized with an expression using
819 /// other constant values.
821 /// This class uses the standard Instruction opcodes to define the various
822 /// constant expressions. The Opcode field for the ConstantExpr class is
823 /// maintained in the Value::SubclassData field.
824 class ConstantExpr : public Constant {
825 friend struct ConstantExprKeyType;
828 ConstantExpr(Type *ty, unsigned Opcode, Use *Ops, unsigned NumOps)
829 : Constant(ty, ConstantExprVal, Ops, NumOps) {
830 // Operation type (an Instruction opcode) is stored as the SubclassData.
831 setValueSubclassData(Opcode);
835 // Static methods to construct a ConstantExpr of different kinds. Note that
836 // these methods may return a object that is not an instance of the
837 // ConstantExpr class, because they will attempt to fold the constant
838 // expression into something simpler if possible.
840 /// getAlignOf constant expr - computes the alignment of a type in a target
841 /// independent way (Note: the return type is an i64).
842 static Constant *getAlignOf(Type *Ty);
844 /// getSizeOf constant expr - computes the (alloc) size of a type (in
845 /// address-units, not bits) in a target independent way (Note: the return
848 static Constant *getSizeOf(Type *Ty);
850 /// getOffsetOf constant expr - computes the offset of a struct field in a
851 /// target independent way (Note: the return type is an i64).
853 static Constant *getOffsetOf(StructType *STy, unsigned FieldNo);
855 /// getOffsetOf constant expr - This is a generalized form of getOffsetOf,
856 /// which supports any aggregate type, and any Constant index.
858 static Constant *getOffsetOf(Type *Ty, Constant *FieldNo);
860 static Constant *getNeg(Constant *C, bool HasNUW = false, bool HasNSW =false);
861 static Constant *getFNeg(Constant *C);
862 static Constant *getNot(Constant *C);
863 static Constant *getAdd(Constant *C1, Constant *C2,
864 bool HasNUW = false, bool HasNSW = false);
865 static Constant *getFAdd(Constant *C1, Constant *C2);
866 static Constant *getSub(Constant *C1, Constant *C2,
867 bool HasNUW = false, bool HasNSW = false);
868 static Constant *getFSub(Constant *C1, Constant *C2);
869 static Constant *getMul(Constant *C1, Constant *C2,
870 bool HasNUW = false, bool HasNSW = false);
871 static Constant *getFMul(Constant *C1, Constant *C2);
872 static Constant *getUDiv(Constant *C1, Constant *C2, bool isExact = false);
873 static Constant *getSDiv(Constant *C1, Constant *C2, bool isExact = false);
874 static Constant *getFDiv(Constant *C1, Constant *C2);
875 static Constant *getURem(Constant *C1, Constant *C2);
876 static Constant *getSRem(Constant *C1, Constant *C2);
877 static Constant *getFRem(Constant *C1, Constant *C2);
878 static Constant *getAnd(Constant *C1, Constant *C2);
879 static Constant *getOr(Constant *C1, Constant *C2);
880 static Constant *getXor(Constant *C1, Constant *C2);
881 static Constant *getShl(Constant *C1, Constant *C2,
882 bool HasNUW = false, bool HasNSW = false);
883 static Constant *getLShr(Constant *C1, Constant *C2, bool isExact = false);
884 static Constant *getAShr(Constant *C1, Constant *C2, bool isExact = false);
885 static Constant *getTrunc(Constant *C, Type *Ty, bool OnlyIfReduced = false);
886 static Constant *getSExt(Constant *C, Type *Ty, bool OnlyIfReduced = false);
887 static Constant *getZExt(Constant *C, Type *Ty, bool OnlyIfReduced = false);
888 static Constant *getFPTrunc(Constant *C, Type *Ty,
889 bool OnlyIfReduced = false);
890 static Constant *getFPExtend(Constant *C, Type *Ty,
891 bool OnlyIfReduced = false);
892 static Constant *getUIToFP(Constant *C, Type *Ty, bool OnlyIfReduced = false);
893 static Constant *getSIToFP(Constant *C, Type *Ty, bool OnlyIfReduced = false);
894 static Constant *getFPToUI(Constant *C, Type *Ty, bool OnlyIfReduced = false);
895 static Constant *getFPToSI(Constant *C, Type *Ty, bool OnlyIfReduced = false);
896 static Constant *getPtrToInt(Constant *C, Type *Ty,
897 bool OnlyIfReduced = false);
898 static Constant *getIntToPtr(Constant *C, Type *Ty,
899 bool OnlyIfReduced = false);
900 static Constant *getBitCast(Constant *C, Type *Ty,
901 bool OnlyIfReduced = false);
902 static Constant *getAddrSpaceCast(Constant *C, Type *Ty,
903 bool OnlyIfReduced = false);
905 static Constant *getNSWNeg(Constant *C) { return getNeg(C, false, true); }
906 static Constant *getNUWNeg(Constant *C) { return getNeg(C, true, false); }
907 static Constant *getNSWAdd(Constant *C1, Constant *C2) {
908 return getAdd(C1, C2, false, true);
910 static Constant *getNUWAdd(Constant *C1, Constant *C2) {
911 return getAdd(C1, C2, true, false);
913 static Constant *getNSWSub(Constant *C1, Constant *C2) {
914 return getSub(C1, C2, false, true);
916 static Constant *getNUWSub(Constant *C1, Constant *C2) {
917 return getSub(C1, C2, true, false);
919 static Constant *getNSWMul(Constant *C1, Constant *C2) {
920 return getMul(C1, C2, false, true);
922 static Constant *getNUWMul(Constant *C1, Constant *C2) {
923 return getMul(C1, C2, true, false);
925 static Constant *getNSWShl(Constant *C1, Constant *C2) {
926 return getShl(C1, C2, false, true);
928 static Constant *getNUWShl(Constant *C1, Constant *C2) {
929 return getShl(C1, C2, true, false);
931 static Constant *getExactSDiv(Constant *C1, Constant *C2) {
932 return getSDiv(C1, C2, true);
934 static Constant *getExactUDiv(Constant *C1, Constant *C2) {
935 return getUDiv(C1, C2, true);
937 static Constant *getExactAShr(Constant *C1, Constant *C2) {
938 return getAShr(C1, C2, true);
940 static Constant *getExactLShr(Constant *C1, Constant *C2) {
941 return getLShr(C1, C2, true);
944 /// getBinOpIdentity - Return the identity for the given binary operation,
945 /// i.e. a constant C such that X op C = X and C op X = X for every X. It
946 /// returns null if the operator doesn't have an identity.
947 static Constant *getBinOpIdentity(unsigned Opcode, Type *Ty);
949 /// getBinOpAbsorber - Return the absorbing element for the given binary
950 /// operation, i.e. a constant C such that X op C = C and C op X = C for
951 /// every X. For example, this returns zero for integer multiplication.
952 /// It returns null if the operator doesn't have an absorbing element.
953 static Constant *getBinOpAbsorber(unsigned Opcode, Type *Ty);
955 /// Transparently provide more efficient getOperand methods.
956 DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Constant);
958 /// \brief Convenience function for getting a Cast operation.
960 /// \param ops The opcode for the conversion
961 /// \param C The constant to be converted
962 /// \param Ty The type to which the constant is converted
963 /// \param OnlyIfReduced see \a getWithOperands() docs.
964 static Constant *getCast(unsigned ops, Constant *C, Type *Ty,
965 bool OnlyIfReduced = false);
967 // @brief Create a ZExt or BitCast cast constant expression
968 static Constant *getZExtOrBitCast(
969 Constant *C, ///< The constant to zext or bitcast
970 Type *Ty ///< The type to zext or bitcast C to
973 // @brief Create a SExt or BitCast cast constant expression
974 static Constant *getSExtOrBitCast(
975 Constant *C, ///< The constant to sext or bitcast
976 Type *Ty ///< The type to sext or bitcast C to
979 // @brief Create a Trunc or BitCast cast constant expression
980 static Constant *getTruncOrBitCast(
981 Constant *C, ///< The constant to trunc or bitcast
982 Type *Ty ///< The type to trunc or bitcast C to
985 /// @brief Create a BitCast, AddrSpaceCast, or a PtrToInt cast constant
987 static Constant *getPointerCast(
988 Constant *C, ///< The pointer value to be casted (operand 0)
989 Type *Ty ///< The type to which cast should be made
992 /// @brief Create a BitCast or AddrSpaceCast for a pointer type depending on
993 /// the address space.
994 static Constant *getPointerBitCastOrAddrSpaceCast(
995 Constant *C, ///< The constant to addrspacecast or bitcast
996 Type *Ty ///< The type to bitcast or addrspacecast C to
999 /// @brief Create a ZExt, Bitcast or Trunc for integer -> integer casts
1000 static Constant *getIntegerCast(
1001 Constant *C, ///< The integer constant to be casted
1002 Type *Ty, ///< The integer type to cast to
1003 bool isSigned ///< Whether C should be treated as signed or not
1006 /// @brief Create a FPExt, Bitcast or FPTrunc for fp -> fp casts
1007 static Constant *getFPCast(
1008 Constant *C, ///< The integer constant to be casted
1009 Type *Ty ///< The integer type to cast to
1012 /// @brief Return true if this is a convert constant expression
1013 bool isCast() const;
1015 /// @brief Return true if this is a compare constant expression
1016 bool isCompare() const;
1018 /// @brief Return true if this is an insertvalue or extractvalue expression,
1019 /// and the getIndices() method may be used.
1020 bool hasIndices() const;
1022 /// @brief Return true if this is a getelementptr expression and all
1023 /// the index operands are compile-time known integers within the
1024 /// corresponding notional static array extents. Note that this is
1025 /// not equivalant to, a subset of, or a superset of the "inbounds"
1027 bool isGEPWithNoNotionalOverIndexing() const;
1029 /// Select constant expr
1031 /// \param OnlyIfReducedTy see \a getWithOperands() docs.
1032 static Constant *getSelect(Constant *C, Constant *V1, Constant *V2,
1033 Type *OnlyIfReducedTy = nullptr);
1035 /// get - Return a binary or shift operator constant expression,
1036 /// folding if possible.
1038 /// \param OnlyIfReducedTy see \a getWithOperands() docs.
1039 static Constant *get(unsigned Opcode, Constant *C1, Constant *C2,
1040 unsigned Flags = 0, Type *OnlyIfReducedTy = nullptr);
1042 /// \brief Return an ICmp or FCmp comparison operator constant expression.
1044 /// \param OnlyIfReduced see \a getWithOperands() docs.
1045 static Constant *getCompare(unsigned short pred, Constant *C1, Constant *C2,
1046 bool OnlyIfReduced = false);
1048 /// get* - Return some common constants without having to
1049 /// specify the full Instruction::OPCODE identifier.
1051 static Constant *getICmp(unsigned short pred, Constant *LHS, Constant *RHS,
1052 bool OnlyIfReduced = false);
1053 static Constant *getFCmp(unsigned short pred, Constant *LHS, Constant *RHS,
1054 bool OnlyIfReduced = false);
1056 /// Getelementptr form. Value* is only accepted for convenience;
1057 /// all elements must be Constant's.
1059 /// \param OnlyIfReducedTy see \a getWithOperands() docs.
1060 static Constant *getGetElementPtr(Constant *C, ArrayRef<Constant *> IdxList,
1061 bool InBounds = false,
1062 Type *OnlyIfReducedTy = nullptr) {
1063 return getGetElementPtr(
1064 C, makeArrayRef((Value * const *)IdxList.data(), IdxList.size()),
1065 InBounds, OnlyIfReducedTy);
1067 static Constant *getGetElementPtr(Constant *C, Constant *Idx,
1068 bool InBounds = false,
1069 Type *OnlyIfReducedTy = nullptr) {
1070 // This form of the function only exists to avoid ambiguous overload
1071 // warnings about whether to convert Idx to ArrayRef<Constant *> or
1072 // ArrayRef<Value *>.
1073 return getGetElementPtr(C, cast<Value>(Idx), InBounds, OnlyIfReducedTy);
1075 static Constant *getGetElementPtr(Constant *C, ArrayRef<Value *> IdxList,
1076 bool InBounds = false,
1077 Type *OnlyIfReducedTy = nullptr);
1079 /// Create an "inbounds" getelementptr. See the documentation for the
1080 /// "inbounds" flag in LangRef.html for details.
1081 static Constant *getInBoundsGetElementPtr(Constant *C,
1082 ArrayRef<Constant *> IdxList) {
1083 return getGetElementPtr(C, IdxList, true);
1085 static Constant *getInBoundsGetElementPtr(Constant *C,
1087 // This form of the function only exists to avoid ambiguous overload
1088 // warnings about whether to convert Idx to ArrayRef<Constant *> or
1089 // ArrayRef<Value *>.
1090 return getGetElementPtr(C, Idx, true);
1092 static Constant *getInBoundsGetElementPtr(Constant *C,
1093 ArrayRef<Value *> IdxList) {
1094 return getGetElementPtr(C, IdxList, true);
1097 static Constant *getExtractElement(Constant *Vec, Constant *Idx,
1098 Type *OnlyIfReducedTy = nullptr);
1099 static Constant *getInsertElement(Constant *Vec, Constant *Elt, Constant *Idx,
1100 Type *OnlyIfReducedTy = nullptr);
1101 static Constant *getShuffleVector(Constant *V1, Constant *V2, Constant *Mask,
1102 Type *OnlyIfReducedTy = nullptr);
1103 static Constant *getExtractValue(Constant *Agg, ArrayRef<unsigned> Idxs,
1104 Type *OnlyIfReducedTy = nullptr);
1105 static Constant *getInsertValue(Constant *Agg, Constant *Val,
1106 ArrayRef<unsigned> Idxs,
1107 Type *OnlyIfReducedTy = nullptr);
1109 /// getOpcode - Return the opcode at the root of this constant expression
1110 unsigned getOpcode() const { return getSubclassDataFromValue(); }
1112 /// getPredicate - Return the ICMP or FCMP predicate value. Assert if this is
1113 /// not an ICMP or FCMP constant expression.
1114 unsigned getPredicate() const;
1116 /// getIndices - Assert that this is an insertvalue or exactvalue
1117 /// expression and return the list of indices.
1118 ArrayRef<unsigned> getIndices() const;
1120 /// getOpcodeName - Return a string representation for an opcode.
1121 const char *getOpcodeName() const;
1123 /// getWithOperandReplaced - Return a constant expression identical to this
1124 /// one, but with the specified operand set to the specified value.
1125 Constant *getWithOperandReplaced(unsigned OpNo, Constant *Op) const;
1127 /// getWithOperands - This returns the current constant expression with the
1128 /// operands replaced with the specified values. The specified array must
1129 /// have the same number of operands as our current one.
1130 Constant *getWithOperands(ArrayRef<Constant*> Ops) const {
1131 return getWithOperands(Ops, getType());
1134 /// \brief Get the current expression with the operands replaced.
1136 /// Return the current constant expression with the operands replaced with \c
1137 /// Ops and the type with \c Ty. The new operands must have the same number
1138 /// as the current ones.
1140 /// If \c OnlyIfReduced is \c true, nullptr will be returned unless something
1141 /// gets constant-folded, the type changes, or the expression is otherwise
1142 /// canonicalized. This parameter should almost always be \c false.
1143 Constant *getWithOperands(ArrayRef<Constant *> Ops, Type *Ty,
1144 bool OnlyIfReduced = false) const;
1146 /// getAsInstruction - Returns an Instruction which implements the same operation
1147 /// as this ConstantExpr. The instruction is not linked to any basic block.
1149 /// A better approach to this could be to have a constructor for Instruction
1150 /// which would take a ConstantExpr parameter, but that would have spread
1151 /// implementation details of ConstantExpr outside of Constants.cpp, which
1152 /// would make it harder to remove ConstantExprs altogether.
1153 Instruction *getAsInstruction();
1155 void destroyConstant() override;
1156 void replaceUsesOfWithOnConstant(Value *From, Value *To, Use *U) override;
1158 /// Methods for support type inquiry through isa, cast, and dyn_cast:
1159 static inline bool classof(const Value *V) {
1160 return V->getValueID() == ConstantExprVal;
1164 // Shadow Value::setValueSubclassData with a private forwarding method so that
1165 // subclasses cannot accidentally use it.
1166 void setValueSubclassData(unsigned short D) {
1167 Value::setValueSubclassData(D);
1172 struct OperandTraits<ConstantExpr> :
1173 public VariadicOperandTraits<ConstantExpr, 1> {
1176 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(ConstantExpr, Constant)
1178 //===----------------------------------------------------------------------===//
1179 /// UndefValue - 'undef' values are things that do not have specified contents.
1180 /// These are used for a variety of purposes, including global variable
1181 /// initializers and operands to instructions. 'undef' values can occur with
1182 /// any first-class type.
1184 /// Undef values aren't exactly constants; if they have multiple uses, they
1185 /// can appear to have different bit patterns at each use. See
1186 /// LangRef.html#undefvalues for details.
1188 class UndefValue : public Constant {
1189 void *operator new(size_t, unsigned) = delete;
1190 UndefValue(const UndefValue &) = delete;
1192 explicit UndefValue(Type *T) : Constant(T, UndefValueVal, nullptr, 0) {}
1194 // allocate space for exactly zero operands
1195 void *operator new(size_t s) {
1196 return User::operator new(s, 0);
1199 /// get() - Static factory methods - Return an 'undef' object of the specified
1202 static UndefValue *get(Type *T);
1204 /// getSequentialElement - If this Undef has array or vector type, return a
1205 /// undef with the right element type.
1206 UndefValue *getSequentialElement() const;
1208 /// getStructElement - If this undef has struct type, return a undef with the
1209 /// right element type for the specified element.
1210 UndefValue *getStructElement(unsigned Elt) const;
1212 /// getElementValue - Return an undef of the right value for the specified GEP
1214 UndefValue *getElementValue(Constant *C) const;
1216 /// getElementValue - Return an undef of the right value for the specified GEP
1218 UndefValue *getElementValue(unsigned Idx) const;
1220 /// \brief Return the number of elements in the array, vector, or struct.
1221 unsigned getNumElements() const;
1223 void destroyConstant() override;
1225 /// Methods for support type inquiry through isa, cast, and dyn_cast:
1226 static bool classof(const Value *V) {
1227 return V->getValueID() == UndefValueVal;
1231 } // End llvm namespace